https://www.space.com/40823-life-on-mars-organic-methane.html?utm_source=notification
Life on Mars? There may be ancient traces.
by CJ | Jun 7, 2018 | Journal | 15 comments
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Dang. The little rover that still can. It just keeps going and going. Amazing.
I’m sorry. I can’t hear about “life on Mars” without thinking of this: https://youtu.be/v–IqqusnNQ
We so, so need to go to Mars (and I so, so want the first man on Mars to be a wo-man).
So, we’ve got two inconclusive but significant clues. One, methane fluctuation seasonally that might be either a by-product of life processes, or might be from geological activity such as vulcanism or maybe ice melt and refreeze. Two, we’ve got older evidence now of more organic molecules, but these might be from other things going on, on Mars, or from life billions of years ago, but we’ve got no conclusive fossils of, say, bacteria or other microorganisms, and definitely nothing multi-cellular; the latter of which would be big news. Even micro-life would be big news. IIRC, they found, a few years ago, some inconclusive shapes in meteorites or rock nodules that might or might not be fossil bacteria / micro-life. But I don’t recall if those were on Mars or Earth.
Could there be microscopic lifeforms, something like photosynthetic bacteria, that lives near or trapped inside, Martian ice? Something like lichens, say? As I recall, on Earth, we’ve got about three distinct types of bacteria that have photosynthesis, but I don’t recall the scientific names for sure. Cyanobacteria is one, blue-green algae; there’s a reddish-purplish-brownish kind, erythro- or rhode-; and there’s regular chlorophyll bacteria, yellow-green. Maybe I’m forgetting a fourth. College freshman biology I and II were, wow, 30 to 34 years ago for me. But as I recall, those and the lichens can live in the Arctic on Earth. (Lichens, however, are multi-cellular, a symbiotic colony organism made up of fungi and algae clumped together. Odd but real.) And slime-molds are likewise, but a different sort of symbiotic…which are motile.
If there are lifeforms like that near any kind of above-ground, in-ground, or below-ground water or ice or water-vapor sources, then maybe. Or, hmm, hydrothermal, somehow? There must be underground spaces like caverns, tunnels, tiny capillary spaces. Leftovers from early or current geological activity of some sort. So if there’s water around any of those, some sort of life might have survived and adapted from an earlier life-abundant past.
The possibility of geothermal or hydrocarbon vents, though, would mean other sorts of life might have existed and maybe those have lingered.
Hmm, one thought: After some billions of years where life was almost entirely but not quite wiped out on Mars, coupled with geological processes before things cooled down and most geologic activity has (we think?) stopped, then weathering, erosion, occurs — What would happen to fossilized lifeforms over millions or billions of years? Would the fossilized structures trapped in the rock matrices be ground up, eroded and re-formed into rocks so much that fossil evidence of complex multi-cellular organisms (such as those big enough to see without a microscope) might become super rare, and the rest might be ground into dust, leaving only those traces of organic compounds without biological structure? Hmm, it seems like, on a planetary scale, you’d still have evidence of fossil complex life, biological structures, evident, peppered throughout the whole planet’s surface.
We don’t quite know what happened on Mars, though. something apparently slammed into it enough to make it a “lopsided sphere,’ sort of like you shaved off or punched a not-quite-inflated ball and got a slightly misshapen sphere out of it. Something led to the loss of much of Mars’ atmosphere from what they estimate was similar to Earth, though smaller, early in Mars’ history, or more than once. Could that have been so violent, say thermally, on the ground and in the atmosphere, that most (not all) life on the surface and much in the water, might have been either burnt up or asphyxiated, due to lack of breathable air and extreme heat, or ash? — In other words, life on the surface might have survived in isolated spots, or might have died out very slowly over time, depending upon how badly the planet was hit. So if life existed, which seems likely, then maybe it had time to adapt, either in several forms, or only from a small number of forms, depending on how sudden or slow or large-scale the processes were which led from earlier abundant water and air, to current arid, here, cold conditions.
It still seems like there could be conditions favorable for something very dang tenacious to have hung on. If those dang Tardigrade little guys can survive for brief periods, maybe even advanced critters like them could find a way to make it, over time. Maybe. Even if it’s only low-level stuff like lichens or slime-molds or fungi, that’s still pretty impressive. Creatures like Tardigrades or anything that complex would be extremely impressive. (Actually, I suppose both Tardigrades and lichens and slime-molds are all roughly as complex, though the Tardigrades show somewhat more complexity and organization in structures.)
So … Well, the article doesn’t say we’ve definitely found life. It says we’ve only found more evidence supporting either/or and the possibility of conditions for life earlier on Mars. So still, good news toward the possibility we still might find it somewhere, either fossilized, or extant.
Even fossils of complex life on Mars would be a huge deal. Living organisms of any complexity would be a huge deal. — Likewise on Jupiter’s or Saturn’s moons.
That we’re finding more and more to support the possibility that there was life on Mars in its very early history, sure is interesting, and sure is a precaution about protecting life here. … If only governments and corporations would pay attention and keep it in mind, instead of all that quarreling. — Life will find a way, though, surely. Strange thought: Even if humans don’t make it, something else on Earth might. — As evolution continues, wouldn’t several forms tend to evolve toward intelligence and tool-use, or towards other forms of sentience / sapience that don’t go in the same direction as humans using tools? (Cetaceans, for example, maybe.) I mean, several mammals and birds and the octopi seem like they could evolve towards intelligence and tool-use, given a chance. — But other (“lower”) forms of life would also be evolving into newer, more complex forms we haven’t seen. So who knows what might be possible even here on Earth. I mean, four-winged dinosaur-bird forms happened, and some truly freaky invertebrates and arthropoda ormed, so there could be lots of things on Earth.
But on Mars or the moons of Jupiter and Saturn, life could be evolving along entirely different paths than what we have on Earth. They’d be “extraterrestrial,” not Earth-like, by definition.
Also of note — I’ve been rewatching Stranger Things, and the animal-plant-fungi-whatevre hybrid-like lifeforms they have in the Upside Down there are really, really alien and fascinating. They’ve done a great job in coming up with a connected biological taxonomy of lifeforms there, besides one huckuva bang-up story, plot, and characters going on. Loving it as much or more on this second time around. Brilliant stuff. Can hardly wait for season 3 to air, probably spring or summer of 2019. Surely among the top ten video SF&F I’ve ever seen. — But yes, the lifeforms they’ve come up with for the show are really bizarre and interesting, and mostly plausible. (The possibly paranormal aspects, we’ll chalk up to more speculative SF&F, but still enjoying those too.)
IIRC This week’s “Space’s Deepest Secrets” had a lucid timeline of Mars’ development and speculation of three periods of possible evolutionary activity on Mars as well places where life might manifest itself. It was a 2-hour program on Science channel and may possibly be rebroadcast on Monday 6:02pm to 8:06 pm Pacific Daylight Time.
“But on Mars or the moons of Jupiter and Saturn, life could be evolving along entirely different paths than what we have on Earth. They’d be ‘extraterrestrial,’ not Earth-like, by definition.”
Only within the limits imposed by the laws of physics and biochemistry, of course, and those impose limits on how much different things can get.
Water is not the only solvent, but it is recognized by chemists as “the best” for its unique properties. Oxygen is not the strongest “oxidizer” such as is used in metabolism, fluorine would be but it’s much too strong, the ultimate chemical pillager — it’ll steal electrons from almost anything, making it much too hard to control. Sulfur is in the same family as oxygen, bacteria at the hydrothermal vents use it–and they’re still just bacteria. Methane is not an oxidizer. Chi and T’Ca may breathe methane, but they need to drink or eat an oxidizer or they’ll have no energy, period. And yes, the Knnn must violate the Laws of Thermodynamics, which we have observational evidence work everywhere in the Universe. All living things are heat engines — we need to somehow eliminate “waste” heat. That’s why you die from “exposure” in Death Valley. When you’re living near absolute zero there’s not much colder than you that you can dump heat to.
Carbon, yep, those four valence electrons are what life needs. Silicon is in the same family, certainly, but it’s bonds are weaker — the technical term is “electronegativity” — chemical bonds would break too easily.
I like to point to the differences between the copper-based hemocyanin of arthropods and molluscs. Life on Earth experimented with oxygen transport, until it found the best. Yes, hemocyanin is a possible oxygen transport, obviously, but it’s only a quarter as effective as hemoglobin. (Yes, scream crab!) In a predatory environment you’d better be using hemoglobin! Even the tube worms from the hydrothermal vents are red. There’s a reason we use ATP for energy storage and production, the chemical reactions just work best.
I think you’ll be hard pressed to find a scientist who doesn’t believe we’ll recognize organic life and our affiliations, when we find it.
@Paul — As before, I was not claiming that absolutely any fantasy would work. As before, of course I was saying, within the bounds of the laws of physics and chemistry.
Other people more knowledgeable than I am have posited there could be untold things within the possibilities of the Terran forms of DNA and RNA. They have also posited there might be other chemical structures besides DNA and RNA that could function similarly. Or that life on other planets and moons might use other things, or combine known things, in ways we humans haven’t thought of. So there are things that have completely surprised biologists in the past century, such as life around hydrothermal deep sea vents, or those highly alkaloid lifeforms, or life far more tolerant to conditions we had previously thought were lethal, extremes of cold, heat, Tardigrades resistant to (but not immune to) outer space conditions, and so on.
So even on Earth, there are things we haven’t considered that did and do exist beyond conditions we currently think are the boundaries for lifeforms.
That left- or right-handedness in chemical structure: All right, there’s a reason that on Earth, we only see the one, but that doesn’t prove it isn’t possible; only that it’s unlikely here. But a single lifeforms found to exhibit would prove it does exist. Until then, we don’t quite know why it was either out-competed here, or if it really is untenable.
Silicon-based life? Methane-breathing life? Scientists have proposed such life could exist. (Silicon-based is also likely to have carbon-based components, as I understand that idea, or might exist solely silicon-based.) But apparently, under the right conditions, either methane-breathers or silicon-based life might be possible, according to, yes, unproven theories.
My point, please, is not to go on wild goose chases. My point is that we only have Earth-based life as the one realm we know exists. But if life is found on Mars, in fossils or extant, or on one of Jupiter’s or Saturn’s likely moons, then that will tell us a great deal about what else is and is not possible. Because since it would have evolved, by definition, there instead of here, everything from its biochemistry to the large-scale biological structures that such life takes, would be “alien” in some way, unexpected. Sure, there might be a great deal in common with Earth-based life. It might well use many of the same things in biochemistry, because certain things are workable and others are not. But neither can we rule out that other processes / molecular structures, or large-scale structures, would work. We don’t know yet, so we can’t rule out postulated theories; or the possibility that we simply haven’t thought of something that “Mother Nature” uses, that could exist, that, if life is found elsewhere, would indeed exist there in that previously unknown, unguessed form.
I am NOT attacking your knowledge of chemistry. I am NOT claiming any fantasy would work. I AM saying, again, that there are, on whatever other worlds (planets and moons) where life exists, all sorts of things about that life which we have not guessed before, and that we’re also likely to see things in some life elsewhere that are similar to how life works here. Really, that is not a crazy or infeasible proposition.
We’ve had that discussion before here on the blog and at Shejidan. I am sorry you insist that such things cannot be, just because we haven’t seen them in Earth life yet, and just because we haven’t yet discovered proof of life elsewhere. But please don’t insist that just because you disagree, that means that what I said is sheer fantasy. I’ve never claimed that we just throw any old thing together and it would work. I’ve always said it’s within our known laws of physics and chemistry, but that our science itself does say that there are more things possible within that science, yes, unproven theories, or things we’ve never guessed would work, right along with what we know works from processes observed in Earth life.
I do not see why you always presume that when I mention that, you think I mean some fantastical, physically and chemically impossible thing. I am sorry you think so, but that is not now, nor has it ever been, what I’ve said or intended. I wish you would understand my intent in bringing up other possibilities, and I wish you would consider that there are things we do not yet know in science, but which manifestly do exist, even if we humans have not yet observed them in our reality. Just because we don’t know everything, does not mean a thing cannot exist. It only means we haven’t observed it yet or we haven’t been clever enough to figure out yet how such a thing might exist, how it might work.
By the way, if we do find life on Mars, or one of those moons, say this century or whenever that might happen, if it exists there, then that would still tell us what things about Earth life work under those conditions, and what brand-new (to us) things can occur on other planets and moons. We would likely see some things we would never have thought could be, simply because on Earth, those did not evolve from non-living matter. But whatever we find elsewhere is not guaranteed to use only what we know of on Earth. Different conditions would make different things more likely to work better. Random chance would lead to things we don’t find on Earth. We would find out a wealth of things we never thought possible. We might even be so challenged by what we find, that we might be unsure if it is “alive” or “sentient” by our current definitions. And if there is other “intelligent” life out there, it might be just as baffled by Earth lifeforms. Just because humans evolved with our form of intelligence and civilization, does not mean that some other intelligence would evolve the kinds of technology and social structures we did. It’s likely they would, but it’s not guaranteed.
Cetaceans, for example, might be intelligent. They’ve even been observed with clumps of vegetation and other items, as gifts to potential mates, indicating those have some behavioral, emotional significance to them. (Or maybe just instinct.) But if cetaceans are intelligent, then their intelligence is, by definition, not the same sort as ours; they don’t have hands and opposable thumbs. Tool usage is nearly impossible for them; though that evidence of gift-giving, and a few other things observed about them, proves they are capable of some things we hadn’t guessed before. So we have to admit the possibility that alien intelligent life could follow patterns that humans do not. Yet it could still exist.
I really wish you’d understand I’m not trying to spout wild fantasy about impossible things. I am exceeding fine with science, evolution, and so on. I know that science is our primary tool to understand how the universe works. I’m not claiming otherwise. Yet whenever I, or others, say anything about the subject, your immediate response is to say all such things are impossible under known science. Please realize people here are not claiming any such thing. I wish you would understand this and re-examine and revise your stance, your assumptions, about where other reasonable people are coming from in the discussion. — And just because I’m irritated about that, please also realize, I can still be on good terms with you. We can agree to disagree on this and still get along. I only am irritated that you seem to assume that because I, or others, say something about the possibilities of life elsewhere, that you think we are engaging in impossible flights of fantasy, rather than simply wondering about boundary conditions, what is possible within the realms of science, what is possible for living organisms, but not yet known or observed or proven here on Earth. Please consider that people are not claiming absolutely anything and everything would be possible. What I and others are saying is that there are things possible that we simply have not observed or guessed or understood as workable, but which can still go right on existing while we humans remain blissfully ignorant of such things.
Wouldn’t it be absolutely wonderful to discover there is more to the universe than we thought possible? There may be beautiful things and terrible alike, but they may exist all the same without our knowledge or despite our insistence that they cannot be.
I wish you’d understand that’s not engaging in impossible and unscientific fantasy. It is saying, within science. When other people say these things, I wish you would please consider that before shooting down all such discussions as patently impossible and unscientific, naive and magical, fantasy thinking. It is not meant to be so by anyone’s discussion here. Please step back and consider so before arguing I, or other people, are claiming nonsense. That is not, nor has it ever been my intention. There are wonderful things in this universe. We know only a tiny fraction of the whole thing. Our understanding is so very limited even now. But that is one of the beautiful things about the universe, and about science. We can still find new things. We can still learn more about this universe. Every day, things happen around us that we cannot sense directly with our senses, and yet those things do exist. (Microscopic and subatomic and quantum processes, for example, occur despite that we don’t detect them unaided.
) I so wish you’d understand what people intend when they’ve discussed this topic here. You had the idea before that I was spouting fantastical nonsense with no basis in science. Instead, I was only considering that there is more to the universe than we presently know for sure. And absolutely, whatever exists in our universe, in this reality, this plane or dimension — Yes, it works by observable, repeatable, testable scientific method. I never would have claimed otherwise. It baffles me that any time I’ve said anything, or others have, you jump in and claim that’s all fantasy, nonsense. — And I have no wish to attack you personally. I only wish to persuade you that you are misunderstanding people’s approach and intent. I am very sorry you misunderstand my meaning. I wish you would see my intent there. I wish you could appreciate my viewpoint instead of dismissing it as folly, impossible, unscientific, fantasy. I don’t have any such intent. I would like it if we could at least agree to disagree. I’m just dismayed again that you misunderstand. As someone grounded in science, I would think you’d be glad of the opportunity to consider other possible avenues, rather than to dismiss them out of hand as impossible.
I’m sorry if you don’t like my opinion or how I express myself. But I meant neither folly nor ill intent or anything against science. I was attempting to explore ideas. I wish you would understand that.
There are more things in Heaven and in Earth than are dreamt of in your Philosophy, oh Horatio.
— Shakespeare
You and I, sir, may disagree, but I shall defend your right to disagree. We can agree to disagree.
— Paraphrase of Voltaire
As two examples of unlikely Earth lifeforms that did exist, consider:
* A four-winged (arms and legs) dinosaur-bird creature discovered in the last 10 years. I don’t recall the scientific name, but it’s been in at least two recent documentaries. Scientists are still debating how the creature could have possibly glided or flown, yet they’re pretty sure it did. There were at least two camps debating competing theories. The trouble is, the existing fossils are so compacted at key points, that it’s not too clear how their joints fitted together or to what extent they could move, and therefore how they could fly with all four limbs and tail, body, and head. But that creature did something. It would have been ungainly on the ground walking. It walked and flew or glided somehow. The creature existed, but how it moved is in hot debate. It’s an amazing small creature, but neither tiny nor huge. It lived. It managed to fly or glide and to walk and probably climb trees, even though scientists don’t agree yet on how.
* Be it noted, scientists still have trouble understanding how bees and hummingbirds fly, and yet they manifestly do quite easily, despite our limited, only partial, understanding of the physics involved.
* An invertebrate, an early arthropod, if I recall correctly, Pre-Cambrian or Cambrian times, I think it was. I don’t know the scientific name and I wish I knew the name of the documentary it was in. It was from before 2000 or 1998, because my parents watched it too. I believe it aired on the Discovery or History channels back then. — This completely strange creature had only partial bilateral symmetry and not radial symmetry. But somewhere in there, its genetics took a sharp turn into the weirdly unlikely. It had a very strange arrangement of body parts, including the head and limbs and thorax. There was something about it having an asymmetrical arrangement of five eyes or other sense organs on the head, and I think there was also a proboscis or grabber arm or tentacle, something out in front that it used for food-gathering or fighting. It was rather flat and elongated and swam in the early oceans. But the main thing is how very oddy its body plan diverged from either kind of symmetry of other animals. If there weren’t fossil evidence, anyone would not believe such a creature was possible. Yet these things swam around and hunted, quite successfully, for a very long time, before an extinction event killed them off or they were out-competed by other lifeforms. (I think it was an extinction event.) — That episode was about the truly bizarre early invertebrates that populated Earth. I believe that was prior to the appearance of fishes and amphibians, and maybe before chordata (animals with a brain and spinal chord, early or just prior to vertebrates).
The same documentary had a great many other unlikely early lifeforms, but that asymmetric critter really stuck out, because it was highlighted as baffling scientists that it could exist, and yet it did.
Evolution can occur at all points on the taxonomic tree of life. It’s ongoing. So new “critters” could appear over time, at any and all points along the tree, innovating in ways we haven’t yet guessed. Heck, there are things such as lichens and slime-molds that are symbiotic organisms, colony-creatures that combine algae and fungi into the overall organism. There are creatures that blur the lines between plants and animals and fungi, both in the single-celled and the multi-cellular levels. So all sorts of things are out there, and more are possible, right here on Earth, in our present day and our future. There are estimates that all the fossil evidence we have is only a tiny fraction of the lifeforms that exist today, so that we have a huge number of lifeforms from our Earth’s past, which are entirely unknown and undiscovered. Right here on Earth, there are lots of things that are possible within the bounds of what DNA and RNA can produce naturally. That’s very exciting.
So even if life on Mars or other planets or moons adheres only to the DNA / RNA bounds, there could still be a wealth of new critters out there in forms we’ve never considered. If it follows some other path, due to different conditions on another planet or moon, if its biochemistry differs somehow, which it could, then there are even more possiblities out there.
That so far, what’s been found on Mars indicates known building blocks, precursors but not life, says the possibility can’t be ruled out that there could have been life there, microscopic single-celled, or multi-cellular, perhaps more complex. That is still tremendously exciting. If there are fossils or if there is extant life, either would revolutionize science and religion. Likewise if one of Jupiter’s or Saturn’s moons proves to have life. And if more than one does, wow, would that be something.
It might be there somewhere. Conditions sound more and more favorable for it to have existed or to exist currently. It would be amazing if that gets proven during our lifetimes.
I have perhaps 23 to 50 more years, depending upon the lifespans of my parens, grandparents, and their siblings. I wish they’d hurry up and get a manned mission to Mars, and really good probes to Mars and the Jovian and Saturnian moons in question. (I’d specify, but I have trouble recalling which three or four are likely. Titan, Europa, Io, and Ganymede, I think, and I may be adding or missing two. I need to look again.) Anyway, it would be wonderful if that could happen. The anniversary of the moon landing is July 20th; 49 years ago this year. We’re still not past the Earth-Moon orbit.
Mars or Bust.
My grandpa always had itchy feet, going between Virginia and Texas. In 1755, my first known (European) ancestors crossed the Atlantic Ocean because they had itchy feet (or some such). — I would be just fine with something reasonably safe, a starship or interplanetary spaceship out into the Solar System or beyond. I doubt I will get to be one of those people now, at 52. But that’s OK. I still would love it if it can happen for some explorers who have that itch for independence and new things. Good for them.
Pyanfar was entirely right about not keeping all those eggs in one basket. being curious about what’s over the horizon is a good thing.
“Man’s reach should exceed his grasp, or what’s a heaven for?”
On a more mundane level, my keyboard’s losing a couple of keys. Time for a replacement.
I think the one with five eyes is Opabinia, found in the Burgess shale. (Most of the critters in it have some relationship to currently-living ones – but that one, I don’t know about.)
(They’re finding even earlier critters in China.)
Oh, thank you; I’ll look that up. — I want to find the documentary that discussed it also. It was a broad survey, I think multiple episodes covering the whole history of life on Earth. Eventually, if it’s available in digital format, I’ll run across the documentary. — Yay, I’ll look up Opabinia. It’d be great to find if that’s the one.
(Dang keyboard is acting up still; at least two keys are trying to die. I have a replacement on order, due in next week. Oh, technology. Keyboards don’t like heavy use, but they like even less when a certain two felines traipse across. This does, however, occasionally result in odd random typing!)
Aha! Opabinia regalis is indeed the critter. Arthropoda or Annelida or something ancestral to both, huh? Hmm, I’ll read the rest of the Wiki article in a bit. Thanks! Cambrian era….
Off-Topic: About Lions
Tangentially Related:
https://youtu.be/9eae-WWnb3I
“BIGGEST GROUP OF MALE LIONS EVER RECORDED – real or fake?”
Watch the video and decide for yourself, but here’s the “jump to the end” version:
The video shows cooperation among a large group of male lions in captivity. There are 14 to 17 male lions walking down a paved road. Sources say they were following a feeding truck, and that the reason they’re getting along is that there are not also females and cubs mixed into the group.
However, to me, this also shows that at necessity, they are intelligent and social enough to get along with each other, to cooperate towards a necessary or rare food or water source, a shared goal that benefits them as a larger but temporary pride.
Some of these lions look similar enough to be brothers, male cousins, or identical twins. Male lions, friends raised together, can form friendships or alliances.
Housecats are known to bring home buddies, or sometimes to “adopt or foster” a younger kitten or adolescent and bring them home to be taken in. (I would presume cougars, in the same genus as cats, could do this.) So possibly lions do this too.
Male lions do occasionally team up with new friends in the wild, though more often, they know each other already.
So this seems like an extension of that under special circumstances.
Shades of hani Hermitage, there.
BCS, Paul, I get the impression you two guys are talking at cross-purposes, and agree more than you may realise.
It looks as if Paul is talking on the micro level of atoms and chemical reactions, and BCS on the macro level of whole creatures and groups/ cultures/ behaviours.
I haven’t been on Shejidan, but this is what I understand from what you both are saying: Paul is talking about the basic biochemistry, the basic atomic-level interactions, molecules and processes that are necessary for life to exist, and are subject to the basic laws of nature (thermodynamics and such). Alien life would need to make use of similar processes, and have access to more or less the same elements of chemistry which are available on earth though in different relative proportions.
They will need to have some form of energy absorption and exchange, a way of growing and exchanging basic information, finding or ingesting some form of food, probably procreating, etc., which at the very micro-level at which biochemistry occurs (if I can phrase it that way, being an ignoramus as far as chemistry goes) will be based on similar reactions between similar elements as happens on earth.
It doesn’t mean they will be the exact same elements: if copper is plentiful but the chemical building blocks for hemoglobin aren’t, those aliens might use hemocyanin instead, or something else which *at a micro chemical level* will fullfill a similar function.
Because the processes life needs will be similar, even if they’re built from other elements – most of whose basic atoms will not be totally unknown to earth scientists, even if life on earth doesn’t use them that way because a better alternative is plentiful here – that means that whatever exhibits those processes will be recognisable to us as a lifeform.
If the chemistry available to the aliens is similar to ours (which within our solar system would be rather likely, though dependent on temperature, atmosphere, pressure etc., but nothing wildly unknown), then throughout their evolution they will be subject to similar optimizations and also, just like earth, to random events and mutations.
This means two things: at the basic molecules and processes level the local alien life will tend to be recognizably similar to earth molecules and processes. Thus alien life forms will be recognizable to us as lifeforms, based on the same stuff the solar system was built from, as is all earth life, from a cyanobacterium to a blue whale.
As is sort of proved by even the weird lopsided 5-eyed creature’s fossil being recognised as a lifeform, from earth…
At the same time, on the macro level of whole creatures, and the organisation and interaction of groups of creatures, that BCS is talking about, those lifeforms might not look like anything we’re used to on earth. What if something like that lopsided 5-eyed creature didn’t get wiped out, but stood at the basis for the alien speciation? That might result in lots of lifeforms with no radial nor bilateral symmetry, and maybe a few outliers with symmetry. Even if symmetry is more efficient, natural mutations and selections (maybe combined with isolation) can lead to some less than optimal end results (like the inversion in the human eye), which can persist even if they’re not the optimal solution as long as they work and don’t create a great disadvantage in handing on one’s genes.
So their exterior might be very different from anything we’re used to (you just have to look at tge weird extinct creatures from the pré-Cambian (?) explosion of life, before the first mass extinction, to see that the external shapes of living creatures can be wildly different from present-day examples, and still work as animals and plants etc.
At the level of algae and single-celled organisms, recognising them as life is about as far as we can go towards understanding them anyway: we can try to understand how different aspects of their life work, but we’ll never have a conversation, an exchange of ideas with them (neither with an earth algae nor with a martian one), as they are not capable of that level of abstraction.
If Europa or Io turn out to have alien fish swimming under their frozen surface, I fear we won’t be able to communicate with those any better than with our earth aquarium fishies.
And if some of them, like some of our own cetaceans (and crows, gorillas, chimps etc), might be intelligent and capable of a conversation? We haven’t even been able to make that connection on earth, yet…
I know that a few human-raised chimps have been taught to communicate through a keyboard with pictures, but that’s not exactly the kind of alien contact BCS likes to speculate about. That’s not to say such contact is impossible in theory, just that up to now humans haven’t demonstrated much aptitude for it.
Maybe the best we can hope for if such contact with e.g. a cetacean-equivalent on Io ever occurs is that we will recognise it as an alien lifeform (likely, as Paul says), and decide to leave it on peace on its own world(moon) without disturbing its habitat. Not likely, from what humanity has demonstrated so far.
If we do find single-celled life on Mars, or even multi-celled, it will certainly not deter us from exploring and conquering Mars and thus ultimately destroying its habitat. We’ve not let finding other humans occupying “newly discovered” territory deter us from doing so if there’s a profit to be made from it. Exploring space is costly, I’m sure people will be out to recoup those costs eventually.
About a year or two ago, there was a previous discussion on the possibilities for life. This expanded into a discussion on Shejidan, but unfortunately, it got sidetracked into an argument over approaches, or over whether such things were scientifically possible, or were flights of fantasy that were impossible. I’m afraid Paul and I, and others, got into an unproductive and unfortunate (and mutually unwanted) head-butting argument about whether it was all science or fantasy.
I let that color my rebuttal here too much, and I regret that.
Paul means well, but is unwilling to accept theories (posited by other scientists with biology and chemstry backgrounds far more complete than mine). I have no real basis to judge that, other than that things like methane-breathing or silicon life, or some others, are deemed possible by those scientists, while Paul rejects those as either too implausible or outright impossible — and then goes on to dismiss other things said (by me or others) as either fantasy or too unworkable, and then brings physics into it. But I haven’t ever claimed that in this, our reality, that things would not abide by the laws of physics or chemistry. I agree they have to, with the implicit caveat that we sometimes have to revise our knowledge in all areas of science, to encompass new findings and new, improved or refined theories. (Heck, DNA and inheritance themselves don’t date back prior to the 19th century (Mendellian heritability) and mid-20th century (Watson and Crick on DNA discovery).
Yes, my own viewpoint is more on the large-scale of whole organisms, social structures, the complex shapes life can take. My own scientific training for biology goes as far as an intro/survey course, two semesters, lecture and lab, and I made an A in high school chemistry and liked it, but did not have it in college. (Where I went, freshman or sophomore organic chemistry were weed-out courses for all the biology, medicine, veterinary, and various engineering students.)
One thing I’d seen recently was a discussion saying that scientists had discovered a kind of workable DNA or RNA analogue, not known on Earth, but demonstrated in lab experiments and papers, wherein different building blocks were used, rather than the A, T, C, G used in all Earth DNA. The article (video) said they were very excited, as it showed that life elsewhere might use an analogue of DNA or RNA, and further, it implied certain other analogues might also be possible, workable. — It’s this sort of thing I’m referring to also. Working science pushes back the boundaries every day, proving or disproving hypotheses and theories, calling for revisions and retesting, to refine what we know. And then occasionally something comes along and hits us all over the head (figuratively, we hope) and says, well, look at that, you humans never guessed this, and yet here it is. Once in a while, that’s even very basic science, sometimes from school kids. And that’s great. It keeps us all refreshed.
Or take an area I know a bit more about and also don’t know fully: There’s this whole range of time from the last Ice Age with modern humans and the last Neanderthals (and some other hominids, maybe) but mostly modern humans (Cro-Magnon and later). From then up until the Bronze Age, we have only bits and pieces of things. But as far as we know, every human language and culture in recorded history and any still existing today, all date to the early Bronze Age. We know there were human cultures and languages that existed before then. We do have a few artifacts, mounds, stone structures from Neolithic times. We know there must have been groups that preceded the Bronze Age cultures, that gave rise to them. But we don’t really know much about them. That’s a huge period from 30 to 35 thousand years ago, up to the start of the Bronze Age, which was sometime before 10 or 6 thousand years ago. (I’m fuzzy on that date, sorry.) The point being, whole primitive civilizations and language-groups had plenty of time to rise and fall in that length of time. Some might have reached levels comparable to early cultures we know about. But we don’t (yet) have evidence of those to any great extent prior to the Bronze Age. — The entire Indo-European language family dates from the Bronze Age, everything from Sanskrit, Persian, Hittite and others, to nearly all the familiar ancestors of the European languages except Basque, Etruscan, maybe Minoan, and the Finno-Ugric languages (far north) and Hungarian (Magyar). There were cultures in Europe that were displaced (conquered or killed or inter-merged) in Europe and in India before then. We have evidence of those, artifacts and recorded bits in history, plus what might be oral history in myth/legend. But we just don’t know much about the people that were there.
I am sorry that, elsewhere, we got into something unproductive over whether various things were possible or impossible, science or fantasy. My intent was not that. My intent was more along the lines of, there are these various ideas around about what might be possible for life, actual scientific theories. There are things like the iron-based and copper-based blood, with yes, the very properties Paul said. (Our biology lectures went into that as being why, on Earth, hemoglobin and red blood is seen more than hemocyanin (blue-green blood) in some invertebrates. The latter is less efficient, but is still useful enough that many organisms still use it.) — Or the recent bit about analogous DNA types, or the chirality (left or right) bit, or alkaloids, or a host of other things.
I freely admit I don’t have the chemistry knowledge to go over those in detail. Yet that wasn’t my point. My point was about exploring, considering ideas, or what might be possible out there.
So maybe more of a macro level. I don’t know what might be out there. I think various ideas proposed are worth consideration. If they could work, why not test them, see if they do work?
There are bound to be things out there we’ve never thought of; they’re so different, we’ve never considered them. Or our current science doesn’t understand them, to greater or lesser extent. Or, as always, our current science may need heavy revision, because we just don’t know enough, our ideas can be way off sometimes. That is also how science works.
I over-reacted earlier today based on that prior argument. Paul, I’m sorry about that. My point, to please reconsider your stance, and what other people’s intent is in the discussion, still stands.
I think the estimate was that of all life that has ever existed on Earth, what lifeforms now exist account for the vast majority about which we know, with everything we know of from the fossil record being far less than what lifeforms are alive currently, and therefore, we know something less than 10% (or was it 1% or 2%) of what we can estimate existed, by comparing to the diversity of life today.
Then we have whatever might be (yes, chemically) possible to arise on Mars, or the moons around Jupiter or Saturn. — We don’t yet have any proof there is life there, but we have really tantalizing evidence of some of the basic building blocks on Mars and on, what, one or two moons each of Jupiter and Saturn? — It seems likely we could find fossil or extant life on Mars. All the right conditions were there, as we understand it, in the distant past on Mars, when it had water in all three classic states, organic compounds, an atmosphere, geologic activity to produce heat and other things, and so on. And something like four moons beyond the Asteroid Belt have conditions either for life as we know it, or life under conditions we speculate might be possible. That’s very exciting and good reason to explore and investigate, to form theories in science on what could work here — or just to have some fun speculating.
Science fiction is about speculating, playing with the ideas, using science as a basis, a jumping-off point. Yes, it’s fiction. — But then, those documentaries on scientific guesses at what alien life might be like, are also a form of science meeting fiction. But that’s great. If we lose play and imagination, we lose something in our ability to do good science, to postulate and test and revise, to keep trying new ideas until something sticks, and revise what does work with even better understandings, or sometimes to throw out one theory and go with a better one.
Paul, I’m sorry if my approach aggravates or baffles you. Honestly, my intent is not to do so. Please understand that and try to see where I’m coming from. I do have some training in sciences and mathematics, but mainly in liberal arts. So my approach is a generalist one, the joy and wonder of science too, or the fun in looking at things, coming up with ideas, seeing what might work. Speculations about lifeforms? Why not do so? Reputable scientists come together from multiple disciplines to approach the topic. — If aliens arrive tomorrow, we’d most assuredly want a broad-spectrum approach to how to understand them as fast as possible. Or likewise, if we ever get off our collective butts as a species and get those probes to the moons of Jupiter and Saturn, then if we find something there, we’ll have overjoyed scientists studying their butts off for centuries, trying to figure out how such things work.
I would like to say also, that I most definitely am a fan of STEM, but I’d prefer we include the arts, for STEAM. My mom was an English major and a professional artist (painter), and also had a background with accounting and business training. She was of the generation where women were told they couldn’t make it in mathematics or other scientific professions, and she encountered that. She considered being a teacher, but our city was already seeing the rise of the inner city problems that now are nearly city-wide in many places. So she had a wide background. My dad was a farm boy who had a natural talent for engineering. He went to college after the Army, got himself through by working in a tool foundry, and got an engineering degree and job before heavier physics and math were required; so he was grandfathered in as a professional engineer, and had a more practical and instinctive knowledge of why you could and couldn’t do a thing in engineering. My dad also grew up with a great love of history, of his area of the country and in general. They both loved books. They were religious (very) but believed in tolerance of other faiths, and in the value o science, things like evolution, and hmm, more love o books. They very purposefully instilled things like that in me. So I’m some mix of those, with a few things of my own, like a higher language interest. It bothers me as much as any science major, when I see people regressing towards unscientific nonsense in schooling or in everyday life. Or the creeping in of old prejudices we need to get over, if we’re going to progress as a nation or a species. I’m an ally, dang it.
And yes, it frustrated me in the former argument, and did today, which is why I rebutted so sharply.
However, I did not mean to react so sharply as to make a personal attack. Even though we sometimes disagree, I also like much that you, Paul, bring to the discussions here. I don’t want any animosity, dislike, or ill will between us. Obviously, I’m very sensitive to that from my own life. I would rather be friendly and get along, and if need be, to agree to disagree on something and go on. But hey, if we could reach common ground, an understanding of each other’s viewpoints, so we don’t go cross-purposes, then that would be even more preferable. — It is sometimes hard to understand others from text alone. Heck, it can be hard to understand each other when face to face in the same room. Funny how that is, for social primates, supposedly such an intelligent species.
Anyway, I’ve taken up way too much space in this blog thread. I would not be surprised if CJ would cheerfully like to soak our collective heads. 🙂 Er, she’s shown usual forbearance, which is appreciated.
One can imagine almost anything, but its worth depends on how factual it is.
Anything is not possible. That which is unknown can not be presumed possible. It is unknown!
Separate fantasy from fact. Fantasy is entertainment. Facts built the Universe.
Facts have consequences, fantasies do not–unless one is on a parapet and fantasizes one can flap one’s arms and fly.
The more uncomfortable a perceived fact is, the more it requires objective analysis and the more unqualified one is to do it.
Extraordinary claims require extraordinary demonstrations of truthfulness.
Science knows some extraordinary things very well indeed, e.g. what the elemental composition of a galaxy 1,000,000,000 light years away is, even what’s between here and there.
Science is self-correcting. It’s very good about knowing how certain it is.
Science does not depend on faith and belief, rather skepticism and demonstration.
Choose one’s authorities judiciously.
Never use ignorance as a justification for anything.
About a point of ignorance, consult authoritative sources.
Accept nothing at “face value”. That coinage is worthless.
(Aspies strongly tend to be unswayed by crowd opinion.)
{Dang, I forgot to bring my hammer and nails.}
Oh, for goodness sakes. That really misses my point, my intent, what I said, and how I said it.
I was not arguing in favor of fantasies or any particular religious viewpoint or of entering religion into it at all. I was most certainly not attacking science.
Last time, I decided it wasn’t productive to prolong the conversation, as I felt no progress toward agreeement was being made. I’d rather not make this worse or draw it out anymore.
Paul, you’ve misunderstood me, as simple as that. I’m just going to let it be. I’m sorry, but you have badly misunderstood where I’m coming from or where I’m going with this at all.
I don’t want to argue with you on it. It isn’t helping anyone to do so.
Whoa, guys! Love you both—enough, enough. We can agree we both have a view of the same elephant, but let’s just agree it’s an elephant and move on before it knocks over the furniture.